THE COEALLIAN ROCKS OP ENGLAND. 297 



we see here a fine development of beds, mostly lying above the 

 Lower Calcareous Grit proper, and representing in time the interval 

 between it and the Coral Rag. To prove this point, if for no other 

 reason, we think it advisable to give yet a third description of the 

 quarry, which, indeed, from its extreme interest, we should be sorry 

 to omit. 



The lower part of this quarry is worked for stone, and the upper 

 for brick ; and the working faces do not coincide ; so that our section 

 is a double one combined, the upper portion having apparently been 

 overlooked by the Survey. 



Section at Highworih South Quarry (fig. 5). 



ft. in. 



1. Rubbly limestone, with prostrate Thecosmilice and 



Cidaris jlorigemma, an irregular bed of varying 

 thickness 1 



2. Laminated current-deposited yellow sands, with 



large white oolitic grains. These oolite grains in 

 various parts form nearly the whole mass of the 

 stone, which then becomes a false-bedded flaggy 

 oolite, with large grains, having a very peculiar 

 appearance. The surface is covered with frag- 

 ments of oysters and Pectens, but none large 

 enough to name specifically 5 



3. Even-bedded sands, becoming dark and argillaceous 



below, and used for bricks. [No. 1 of the Survey 

 section.] 6 



4. Rubbly large-grained oolitic beds, divided irregu- 



larly by layers of soft sandy or fossiliferous oolite, 



the lower parts the hardest. [Nos. 2-4.] 6 6 



5. Ferruginous, rubbly, and somewhat sandy lime- 



stones, mostly made up of prostrate and drifted 

 corals. [No. 5.] 8 



6. Shelly limestone, with oolitic grains. [Part of 



No. 6.] 3 



7. Hard calcareous sandstone, becoming a blue-hearted 



grit, of variable thickness. Average 1 9 



8. Soft white sand, with calcareous doggers, and often 



false-bedded 6 



With regard to the interpretation of this section, we may be sure 

 that Lonsdale would never have called Nos. 2 and 3 Upper Calca- 

 reous Grit, though they are sandy, if he had seen No. 1, and traced 

 it on the line of dip till it enlarges to a true coral-bed, as near 

 Watchfield. It is, indeed, a rubbly and possibly disturbed deposit, 

 but proves at least the higher position of the beds from which it has 

 been derived. Mr. Hull, the Geological Surveyor, on the other 

 hand, confining the term Coral Rag to the Upper Coralline forma- 

 tions, classes all the beds below as Lower Calcareous Grit. To this 

 horizon the lowest bed in this section would be universally referred ; 

 but the beds between, from No. 2 to No. 7, though underlying the 

 Bag, may correspond in character, fossil contents, and time to the 

 rocks which elsewhere occupy the interval. The calcareous portion 

 of them is referred by Lonsdale to the true Coral Rag ; and the 

 intervening beds, corresponding to the marls of Calne, are represented 



